In a plasma processing apparatus, a member in the processing chamber is damaged by plasma. An example of damage by plasma includes wastage of a member (a surface facing plasma or a gap) used in a processing chamber. A reaction product deposited in the processing chamber during plasma processing of the wafer is cleaned and removed by dry cleaning or waferless dry cleaning (WLDC).
Waferless dry cleaning is a process of removing deposit by plasma richly containing oxygen (O) radicals or fluorine (F) radicals, without placing a wafer on a stage. The waferless dry cleaning is repeated during between wafer processes. At this time, not only a surface of the stage, but also an adhesive used in components of the stage is abraded. When wastage amount of an adhesive used in the stage increases, thermal resistance of an abraded portion increases, and thereby local temperature increase of the wafer located near the abraded portion occurs.
As a method of preventing wastage of an adhesive, it has been proposed that labyrinth processing or the like is applied so that an adhesive surface is not visible (see Patent Document 1, for example). It has also been proposed to cover portions exposed to plasma with material that are more plasma resistant (see Patent Document 2, for example).